Non-toxic multinodular goiter

The external surface shows nodularity and varying brown-red color.

Flat, relatively inactive epithelium lines colloid-rich follicles. Epithelial hyperplasia can be seen. The presence of a goiter reflects impaired synthesis of thyroid hormone, often caused by insufficient iodine in the diet. With the initial rise in TSH, there is follicular hyperplasia and hypertrophy. With increased thyroid mass, many patients are able to maintain a euthyroid metabolic state.

Contributed by Dr. Ron DeLellis